Inclusion Criteria:

• Patients with advanced ovarian carcinoma, who have failed one prior platinum and taxane containing regimen
• Only one prior chemotherapy containing either cisplatin or carboplatin plus taxanes administered concomitantly
• At least one measurable lesion according to RECIST
• ECOG performance status 0 or 1
• at least 18 years old
• Adequate haematological function
• Adequate renal and hepatic functions
• Normal coagulation parameters

Exclusion Criteria:

• Platinum-sensitive patients (Group 2) who responded (CR or PR) to a 1st line therapy and subsequently progressed or relapsed after a treatment-free interval of > 12 months
• Pregnant or lactating patients
• Prior treatment with camptothecins
• Presence or history of CNS metastasis or carcinomatous leptomeningitis;
• Current active infection per investigator assessment;
• Unresolved bowel obstruction or subobstruction, uncontrolled Crohn's disease or ulcerative colitis;
• Current history of chronic diarrhea >= grade 1 (CTCAE version 3);
• Surgery or radiotherapy ≤ 4 weeks before first study treatment. In case of cytoreductive surgery for the progression of the disease, ≤ 2 weeks before the 1st study treatment are allowed;
• Other uncontrolled, serious illness or medical condition, as determined by the investigator;
• Concomitant (or within 4 weeks before inclusion) administration of any other experimental drug under investigation;
• Concurrent treatment with any other anti-cancer therapy;
• Known HIV positivity or AIDS-related illness;
• Patients who cannot be regularly followed up for psychological, social, familial or geographic reasons.